I have been testing out some extensions today on tc2.3 during what must have been a heavy load period for the app repository. The repository responsiveness was very sluggish. Both Abiword and ace-of-penquins tce's reported as being installed in a notification box but were not actually "fully" installed. Something went wrong. Neither one had menu or wbar entries and would not execute from aterm but were present in the tce.installed directory. I repeated the process twice and got the same results. I rebooted some time later and tried again. This time the app server was back to normal and the apps installed correctly.
It seems like the app (browser) installer is getting confused when the app server is heavily loaded or sluggish for what ever reason.