I am not entirely sure but on TFTD, I complete my first mission, I get artifacts, but i can only research a select few before unlocking more research items in your inventory... i.e. Plasma Pistol, ==> Plasma Rifle ==> Heavy Plasma
OpenXcom EU.... I complete my first mission, I get artifacts, but i can research ANY item, so can start research Heavy alien weapons immediately? Is this right? Or is it a bug? Or is it something I've missed?? (Never played original EU, just original TFTD!)