Hi Guys! I'm new here (UK)!

[MrChef]

Yep you have to glue the screens on i use a dab of superglue at the corners of the rectangular 1's a use a scalpel to apply the glue on the edges of the round screens

Wise advice, otherwise the glue fills the holes & ruins the finish.

Or I've also used simple PVA white Elmer's glue. Especially on the one's that slot in like the KT or Panther/Jagdpanther. Gives lotsa time to position properly. Of course takes longer to dry. Same advise though be careful not to spread too much onto the screens.