Just started my descent into the world of little devices that need a completely different way of interaction than the full fledged operating systems im used to

Yesterday i started a little project to open up my old alarm system and moving all the motion detectors one by one over to my v2 2866 ESP-12E running on ESP Easy mega 2.0.0. but noticed that i only got response on two motion detectors and 3 other ones do not seem to trigger anything at all. Could be defective sensors but i connected all of them to the working gpio ports and all of them respond nicely. I've also tried older firmware but it doesnt make a difference in which port responds.
So i'm a bit stuck...my thought was that i had around 6 to 7 usable pins but every gpio pin except GPIO0 and GPIO2 do not trigger any status at movement.
I'm sure this is my lack of knowledge so can someone point out what i did wrong or forgot to read?
