All the stuf is in the updates folder as you predicted.
I'll add error log to find out what is the cause, may be access to skins folder is denied for some reason.
Tool works with relative to game binaries paths, not absolute paths, thus it shouldn't matter where game is installed.
I have a question about this tool. If I uploaded a skin and then did some fixes, is it possible to update the skin? Basically make and upload the new skin with the same name?
Although skin versions tracking is supported in skin list format (you can open updates/skindb/skindb.xml and find VersionsHistory tag), updating is not implemented on server yet. Should be available this week a bit later.
I guess it will be in implemented in this way:
1. During skin submission for the first time you will get PIN, some random number like 9253.
2. When updating skin you will enter this PIN, base name, new image/description data and optional comment about changes in the skin.
PIN is required to avoid skin updating by someone else to avoid unintended mistakes or abusing, skin base name/PIN will work like login/password pair.
It may be not the best solution, but I don't like idea of forced user registration.
Originally, skin downloader idea was to develop skin list file format and tool which can work with it.
Having both of them, anyone can provide own skin hosting server and force own politics in skin submission, etc.