Lost in modding - Stash error

Dear All,

I just barely started to learn modding here, reading, reseraching, and doing try-fail-try again routines. Now I faced a new problem, I have no idea how it happens. It’s basically a modification of smash&grab but somehow I have stash issue now.
Do you have any experience having and fixing this or what may cause this?

That is a missing image/texture. No idea why it is missing as you provide next to no info.

I assume either because you have no source file for it (only the .tex), in which case you need to use the archivetool to add it to the .arc after the mod generation, or you have the source but did not generate an asset file for it.