Here are the settings I've got going usually (haven't changed them in a while other than the seed):
(under World Settings)
Method: Wilbur Fractional Brownian Motion (fBm) (could be the difference)
Highest Peak: 30000 ft
Lowest Depth -20000 ft
Circ: 25000 miles (I think these were defaults)
Roughness: 0.45 (I'm wondering if this is the difference here?)
Percent Sea: 43
(these last 3 would be adjusted to taste)
Custom: the maximum number that works under custom (can't remember it off-hand)
I followed on of the tutorials for the Abebe project that was written up for getting more realistic worlds out of FT Pro (it's on their website, I think), which was some processing after (erosion, and a few other things) prior to running rivers.
I hope this helps...I believe the Abebe file, which was in v2 of FTPro died when loaded in v3, but that may have been a temporary issue.
You may need to also adjust the settings under the intensity tab in the colour window.