[Q] installing 3rd party application not working on Cyanogenmod 12 topic

Hey guys i just flashed in Cyanogenmod 12 lollipop 5.0.2 this morning and i tried installing a 3rd party application adilko permium, which i successfully installed before when i was running 4.4.2 kitkat and when my phone was not rooted. when i click on the APK it opens up the installer and lets me click on the install button, then the bar will move for a bit and an x mark will appear and it will say "X App not installed". It also happened to another 3rd party app i was trying to install and yes i do have unknown sources checked. Please, some help will be very appreciated.

i have a samsung galaxy s5 T-mobile variant.