Any special reason why aren't you using Spark *inside* Live 8 as a VST plug-in, that would be the expected way to use it with a DAW that hosts VSTs like Live, IMHO.
...unless you're using 2 computers, each with one of these apps (?!).
Anyway, if you really need to run Spark as a standalone application slaved through MIDI Sync to Live 8, then you may need to mess with Live's MIDI Clock Sync Delay settings for the MIDI port sending MIDI Clock out.
Edit, Preferences, MIDI Sync, click the triangle to open (expand and expose) the settings for the port you're using and try the amount of ms needed to compensate the delay and sync them up.
*IF* you're already using Spark as a plug-in and you're having trouble keeping it "synced" with Live 8, then maybe you're forgetting to turn the "Host" and ""Tempo" buttons ON on the top bar of Spark ?