Hi Guys,
I just downloaded the latest version of UOS from the github page(no OPM involved), extracted the files, then opened uos.lpk from the IDE. After compiling the package the ous.pas is overwritten by Lazarus. Please see attached images for more details. The reason is simple, for every aaa.lpk an aaa.pas is automatically generated by the IDE(I'm not sure why). The fix is also simple, please rename uos.lpk to laz_uos.lpk or any other name, which is not in conflict with a pas file from the same directory.