hi , im not sure what you are doing wrong but spark woks ok in ableton 8.3 for me when i bounce . when you export the file make sure the locators are set to the correct length in the export window. are you making midi loops or using the spark seq for your loops.
Arturia Tester for spark,analog lab2,kl88,matrix12,semv,beatstep,minibrute.se,
ASC,Vcol4, Beatstep pro, VCOL5, Synclavier v.