Welcome to the board Daemos!
I don't grow Vandas because of very dismal light here (sounds like what you have
) But I have a couple suggestions. Can you get compact florescent lights where you live? Something like these
105 Watt Compact Fluorescent If so, you can get a couple very powerful ones and let them run for 12 hours near your plant. It doesn't even need to be near a window if you do this.
As for the bugs, many times on orchids of all types there will be left-over symptoms from the bugs. I also grow cacti and they are much less foregiving of bugs then orchids. Once a cactus gets mites, it's pretty much done. I've sprayed, I've done everything and all I get is scabby growth that looks terrible. With all the humidity from my orchids, though, the last of my cacti are doing really well as evidenced with this photo
This guy bloomed steadily on the main growth plus the pups all summer into the fall - has recently stopped blooming.
I hope you enjoy your visits here in this board. We are generally a friendly bunch and truly international. There are active members from all over the European Union as well as North America, South America, and the far east. Have fun here!