I'm afraid compression can only do so much and some effects just contain too different values from one step to another and can't be compressed very well.
About your other issue (intensity) which dimmer are you using ? RGB lights do not contain any dimmer channel, so all you can do is use a "virtual dimmer" that'll help simulating a dimmer on your color. If you edit it in EDIT mode, it'll save a dimmed version of your color. If you edit it in LIVE mode, it'll save a dimmed LTP version of your color.
You can also use the LIVE scene dimmer, that'll compute in real time a dimmed version of all colors shown in a scene wheile it's being played.
And finally, you have the Master Dimmer that'll do the same thing for all values in your show.
Hope this helps.
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