Default [Q] Polaris office port install qiestion

Hello. I found a Polaris office 5 link which will work with rooted devices Installed as a systems app. I'm rooted, locked BL. After flashing in TWRP it will be there. Trying to open it gives the unfortunately app has stopped message. Looking to clear data in apps it shows no data at all. I go to root explorer find the apk, run in, install new and whamo - works great, no watermark, nothing. However, this is where the problem is, once I restart phone it is back to being uninstalled. It's still in system apps and libs are still there, permission are set. I'm not sure if I missed something. Followed the directions. Searched all over. Is this something to do with being rooted but still having a locked BL? If anyone knows the reason I know where the thank you button is.