I have just begun learning to use the creation kit however I've had some trouble understanding how the save system works and most of the tutorials that i have seen have skimmed over the subject. After loading the data files I started to create a custom interior level by duplicating an existing level, deleting the objects within and then adding my own. I clicked the save button and had to save it as an esm file.

I came back to work on the level at a later date and attempted to save the file again after finishing my adjustments however it asked me to save it as another esm, and wouldnt allow me to overwrite the original as it was "in use". subsequently i have ended up with two esm files.

when going to test these files i found that if i loaded both and used the command "coc" to go to the area only the objects placed after the first save appeared. if i load the original file and try the same command i only get things from before i saved. hence my level is split up between two files and i havent the foggiest how to merge them.

I attempted a copy and paste of the original items into the new file but as it requires me to load both esm files it wont let me save to either of them. even when i save to a new esm i still only end up with half the level. Any ideas what im doing wrong? i know it must be something simple but this is the first time I've tried modding anything so i don't have a clue where to start.

thanks for any help i receive.

You can use Version Control but it's kind of difficult to get working, and there's also the method of duplicating the stuff of one .esp into the other.

To elaborate - open all the esps you want things from as plugin files (filled checkbox next to their name) and then duplicate their entries while you have another ESP that's set as the active file.

Yeah, sorry about that I probably could have gone into more detail on the merging process.

"duplicate their entries..."
would duplicating and renaming an entire interior cell accomplish this?

It's possible.

Silly question:

What does your mod contain, that you need it to be a esm?

Duplicating the entire interior cell accomplishes the process except for custom entries that need to be copied from the Object Window. Things like NPCS, Locations, custom objects, messages, etc. Anything that is not in the vanilla game must be copied along with the reference in the cell being duplicated or the reference is deleted the next time you load the ESP with the duplicated cell.

Edit- you can accomplish that by renaming (not duplicating) the custom object so the in cell references remain intact and point to the copied object.

thanks for the replies, i havent tried them yet as i am not on my gaming comp at the moment.
@Zehryo i dont 'need' it to be an esm but i cannot choose any other options from the dropdown during saving. (as far as i know. i could be missing something i guess)

I'll give all these a shot and will reply with what happens, thanks again.

Chok3hold: renaming the custom item in the object window will automatically rename the instance in the duplicated cell?
Also, does navmesh stay intact with the duplicate cell? I would expect it to, but if it gets hosed in duplication , then it is obviously best to duplicate and combine prior to navmeshing .