as described in the previously quoted release notes, when you send a Mac with Lion to sleep you no longer have a guarantee that your Mac actually sleeps. It'll always turn off your displays. But depending on your settings in System Preferences, it'll either stay awake - or actually sleep. The difference between staying awake and actual sleep can be as tiny as turning on and off File Sharing in System Preferences > Sharing.

It is, however, Lion's default behaviour (and therefore also the behaviour Candelair implements) that, on receiving Apple Remote button presses, your Mac's display is only woken when your entire Mac was previously asleep. Your screen will not be woken by Apple's IR driver (and, again, therefore also with Candelair, which tries to mimic the original driver as close as technically possible) if your Mac wasn't actually sleeping (which, as described above, can often be the case even if you explicitly told your Mac to go to sleep before).

When the problem occurs, please enter

pmset -g live

in Terminal.app and copy and paste the results.

Best regards, 
Felix Schwarz