Hi,
In theory, there is no difference between object and project compile in Siebel but in fact sometimes there is. I crashed a Siebel bug which is related object compile and i wasted lots of time to find the problem 
This is not very common, most of times object compile is working pretty good but in this case below, it doesn’t.
My suggestion is if you are compiling your changes via Object compile and they are not working, please compile your changes via project compile(compile all projects you change) and test it again. It can be related object compile problem.
Regards.
