First of all, start making a backup copy of your NeoLoader folder, expecially the config folder that in the version 0.41f should be under the NeoLoader's one is really important, and your Temp/Incoming folders.
I do not remember if there's the auto updater into the 0.41f, if so, when you did the backup try to auto-update it running NeoSetup.exe (it should be inside NeoLoader folder).
If this feature was not avaible, sorry I don't remember (if there's not NeoSetup.exe, it's not... but it should be avaible I remember it got added at the very beginning) make a clean installation, set the previus incoming/temp folders and copy the filelist.xml into the new installation.
Sorry if this post is too chaotic, I replied quickly because I am busy.
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