Just bought a SNES mini and took it apart to clean it and it came out looking brand new. Only issue I have is the cartridge slot doors that have the springs to close when no cartridge in it aren't working properly now. It appears they are installed correctly but the have no tension to close back by themselves. Thanks.
Considering that SNES mini (snes 2 / snes jr) was released only in US/JAP it's higly unlikely to find the information you are looking for on this forum (especialy that SNES was never released in Romania :D)
Check the spring that is holding the door, maybe you put it back in the wrong position (at least sounds like this is the issue).