The intent is really not to bother anyone or to spam the forum with advertising, but to communicate that these are truly non-trivial problems based on the experience I acquired working on said product's team.
The desktop files are very fickle and work differently on almost all Linux flavors, causing many endless pitfalls. This is the value in using a tool whose job it is precisely to address and isolate you from those differentials, so you can focus on what matters - your application itself.
FWIW, you'd have better luck "reverse engineering" the tool by having it create those desktop files for you on different Linux instances and then comparing the differences, than to actually discover all those nuances by yourself.
I respectfully submit the above to your consideration and thank you very much for your understanding if, due to my previously disclosed involvement with the product, I am not being an objective poster; unbeknownst to myself.