Drumagog 5 Not showing in XP plug-in list

I am running Sonar Producer X1 (X1d), and I am able to see Drumagog 5 in the left hand list of the plug-in manager, so I added it to my custom plug-in list, however, when I go to access the list to add it as an insert it still isn't showing. When I try to show "Default All Plug-Ins" list in the insert process it still isn't showing. Has anyone else seen that?  
To repro -
In Sonar X1 Producer :
go to plug-in manager, add Drumagog 5 to custom list & save.
While on a track, click insert audio plug-in
at this point other plug-ins are visible, but not Drumagog 5
 
I've tried rescanning folders for failed/current plug-ins mulitple times. 
Also, I just tried running Wavelab 7 and it does show up in it's plug-in drop downs, and I was able to add it to the Wavelab session.

Thanks for the input Mike. It wasn't exactly that, but your response made me go back & poke around a bit more. I had put it in the top portion of my custom list & that top portion must have a limit of 13 plug-ins that you can display there (even though the plug-in manager lets you add more than 13). It appears to be in the order they are added, not alphabetical or by location (top of list, bottom, etc...) As soon as I moved it to the lower area it showed up, similar to what you mentioned. I then moved it back up to the top & deleted one of the others I don't use as often & BINGO Drumagog was there.