Ok, I have a little knowledge of theory and would like to compose at least a simple song, to apply some of the theory since its kinda abstract in my head right now, untill I aply it to something. So I got a Chord progression in Aeolian Mode(I think) that is in the key of D.
It goes Dm-Abmaj-Fmaj-Cmaj. after a while it would go to Dm-Amaj-Abmaj-Fmaj-Cmaj. not much of a difference, just thought it sounded cool. So what would I do develop a riff or "solo" around this chord progression. Would I use the Aeolian Scale as well, how would I add "variety" or merge scales some way.
I might be wrong, but I don't think that's an Aeolian progression.

You might be able to use the minor or major scale relating to each chord and simply emphasize some of the new notes introduced by the chord changes.
What you've got there isn't a diatonic progression. Are you sure you don't mean Bbmaj instead of Ab maj?