@Timer
Whether you use admin privileges or not doesn't matter.
The Create feature isn't really complete in the 1.5 release, but that might not be your issue.
There are a thousand things that can go wrong with creating a NORI file with the 1.5 release.
First off, creating 16-bit NORI with palettes is not support by TNT and never will be unless I am forced to by the game's mechanics.
Next, assuming that is not the cause, you still have to change the gawi size (gsize), file size (fsize), and diff size (wogawi) to adjust for the lack of the palette. You might have to adjust bmp info and offsets as well as animation info might need to be adjusted depending on the changes you made.
Also the 1.5 release does not deal with the "extra data section" correctly, so if that is the issue there is nothing TNT 1.5 can do about it. By the way, if the create feature is of interest/importance to you I suggest you look on github about helping fund its completion. I'm no longer working on that feature for free since it distracts from the actual goals of Libre Trickster project.
Just a warning, further discussion of that topic should not happen in this thread.
Most likely, based on your error and overall edit-intention, you probably just forgot to adjust the NORI header and GAWI header information to adjust for the removal of the PAL section. Running out of space before all the bmp have been added is usually a good indicator that this is the problem. Keep in mind, though, that 054 is a v303 with an "extra data section" on every frame, that 053 (v300) does not.