Hi,
Thank you for your patience. The skill system is very complex and, as you know, we can not discuss any details about it. What we can tell you is that if you ever experience frequent CTDs this could explain the perceived loss of skills.
Skills are saved at regular intervals and every time you log out. If you get a CTD before the last skill increase has been registered, then the skills could be lost. So, the issue here is not connected to the avatar or skills in general, but to your regular CTDs.
We are constantly evaluating the crash reports we receive and doing our best to optimize the system in every possible way on our side. However, please note that, on rare occasions, issues that affect the performance of the system do occur, due to technical reasons that are unexpected and unavoidable.
Thank you for understanding and for your participation in Entropia Universe.
Kind regards,
Entropia Universe Support