@Plutoman (and everyone who can help)
What you and Leviathan1753 are doing with ASIS and AV (automatic variants) which are both using Levi's skyproc is absolutely marvellous and pure magic.
Summary: Started using ASIS, have followed it in the past. Did RTFM this thread to the point where it was introduced on here the Nexus. Did RTFM ASIS/PISE Successor Thread #3 on the gamesasforum. Also using Automatic Variants for some time now (quite sure you have seen my posts there). I have NO experience with the CK. I'm trying to understand what ASIS is doing and things I don't know I have to ask ;->
I want to use ASIS for something special and I'm curious if this can be accomplished and how. I'm using Skytest Realistic Animals and Predactors (SRAP) and Real WildLifeSkyrim (RWS) and also Prides of Skyrim (Pride) and More Village Animals (MVA). At this point I ONLY want to change the spawns for these mods (wildlife) and leave the rest to the Skyrim vanilla settings. For example draugr, skeleton, falmer I want to have the normal spawns (no extras). Lets take SRAP as an example. It adds wolfpacks (6-8 wolfs in each pack) and things like herds of Deer and Elk. Unfortunately it adds little extra spawn for rabbits. To keep the question simple. I want to reduce the SIZE of the wolfpacks and increase the number of rabbits in the game say by a factor of five. Do NOT think ASIS can be used to reduce the number of Wolfpack or can it? Looked at the IncreasedSpawn.ini file and I'm baffled.
I'm glad that you are enjoying ASIS and AV so far

! At this point, ASIS does not support increasing the number of spawns for a specific type of creature more than others. However, it is very possible for you to decrease the size of the wolfpacks (or at least, the number of extra wolfs for the packs that ASIS spawns) as well as increase the spawns of only the creatures that you wish. I will detail how to do this later on, as you address the procedure directly in a question.
Questions
1) Can't figure out what the normal change/percentage for extra spawns is for, for example a Draugr or Skeleton. Can't figure out what spawn0weight=200 to spawn5weight=2 do. I only see them introduced but not used in the .ini file.
Essentially, these determine the global nature of ASIS. The values are "weights" for the extra number of spawns indicated by the numeral (0, 1, 2, etc.) in the tag. Whenever an NPC included in the [INCLUDES] part of increasedSpawns.ini is spawned, the game randomly decides how many more to spawn based on these weights. For example, by default, the weights add up to 400. Thus, the change of that number of extra spawns happening is (weight / 400). So there is a 50% (200 / 400) chance of an NPC spawning 0 additional NPCs, a 37.5% (150 / 200) chance of it spawning one additional copy, and so on and so forth. These settings apply to all creatures that ASIS increases the spawns of.
2) Is there an easy way to figure out what the EditorID for a certain NPC/creature is. Is there a list somewhere which I can download or do I have to use the CK or is there another (simpler) tool which could accomplish that. Using the debug files of AV currently and found out that SRAP is adding for example an WolfRedEnc and EncElkBraveST (I assume that are EditorID's). If using a tool do I have to feed it with the Skytest.esp file or?
For me, the best way to find EditorIDs for creatures from the original game is through the CK, but for other plugins, I use TESVSnip to open the plugin and look through the added and changed records for the EditorIDs. However, most times the EditorIDs are pretty easy to guess. For example, all wolves will include "Wolf" in their EditorID.
3) On page five of the PISE thread I read about you talking about NPCMaxSpawnSettings to set the maximum for a certain NPC say Dragon. What exactly does this mean. Is this for whole SKyrim or just the cell where I'm in.
This means that, in all of Skyrim, it will never spawn more extra dragons than the number indicated. Although this section is not included in the default ini file of the download, you can add it to cap extra spawns. For example, adding Dragon=1 under [NPCMaxSpawnSettings] will make it so that ASIS will spawn at most 1 additional dragon for any encounter. Setting it to 0 instead of 1 will effectively exclude Dragons from ASIS.
4) NPCReducedSpawnSettings. Afaik from reading this thread its used for Dragons. How did you find out those name. I assume boss refers to the Ancient Dragon and dragon refers to all other dragons. Could I use NPCReducedSpawnSettings to cap the size of a wolfpack to for example 4. If so how can I find the name to put here. I believe SRAP spawns its own wolves (not vanilla names), not the vanilla ones (vanilla names)
NPCReducedSpawnSettings does not cap the number of additional spawns from ASIS, but rather reduces the chance of spawning extra by the specified factor. For example, with Dragon=5, the chance of ASIS spawning one additional dragon is reduced from 50% (global setting) to 10% (50 / 5). Dragon actually refers to all dragons, including ancient. Boss refers to monsters, such as the super-powerful Draugr at the end of dungeons, that are supposed to be more difficult than the other encounters in a dungeon and serve as "Boss" monsters. In order to find the name to put there, I recommend using TESVSnip to look at the plugin for SRAP and find the EditorID for the wolves somewhere in the list.
5) Have used player.placeatme statements for testing and found out that when I spawn a Dragon there is a change I get 2 Dragons. How big is this change and how is it calculated and how can I change it?
As I mentioned above, the chance to spawn a dragon is the global chance to spawn an additional creature divided by the NPCReducedSpawnSettings entry for dragons. Initially, it is a 10% chance of 1 extra dragon, a 7.5% chance of two extra, and a really small chance of more than that. You can change this by either changing the global settings or changing the Dragon=5 line under [NPCReducedSpawnSettings] to a different number (lower number means more dragon spawns, higher number means less).
Things I think I have to do to accomplish what I want
Disable ALL extra spawns created by ASIS by deleting enc and lvl from the inclusions section. I know what enc means but what does lvl means (leveled list or?). BTW I think SRAP uses its own created leveled lists... Afterwards I assume I have to put ALL NPC's I want to have extra spawns for like Rabbits and Wolves (from the wolv packs) here. Suppose I want the 5 times more rabbits in the game how I do accomplish that ??
I know it are quite a lot of questions. Just trying to figure out what if want if it can be done and how. Hopefully it can be done without me going mental in the process

Yes, lvl stands for a leveled Actor from a leveled list. Yes, deleting Enc and lvl from inclusions and adding the EditorID for rabbits and wolves would make it so that ASIS only spawned additional rabbits and wolves. Unfortunately at this time, ASIS does not support increasing the spawns for one type of character (rabbits) more than another type of character. I can try to add this feature to a later release if you would like me to.
I'm glad you are enjoying ASIS and AV so far! Hopefully my answers helped a little

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EDIT:

. Deleted as I typed the answers lol. Hopefully my responses can still help someone out there O.o!
EDIT 2:
Fixed

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