I actually spent a fair amount of time fiddling around with the row colors and looking through the Qt code that controls this. As far as I can tell, Qt 4.6.2 on Maemo 5 completely delegates rendering of the row background colors to the current GTK+ theme; I don't see any way to easily override it, even using the stylesheet mechanism that works in most other cases. The default theme on the N900 uses black for both normal and alternating row backgrounds, so there's basically no alternating row effect (I'm guessing this was done to save power by reducing the overall screen brightness). If you're getting white as the alternating row color, then I think you've done something to change the default theme. For the time being, the only way to fix this is to use appropriate theme settings. For the next release, I'll try adding a preference to enable or disable alternate row colors; that would let people with appropriate themes use them, but allow the second color to be disabled in cases like yours where it doesn't look right.

I think I can control the text color for the rows, but there's no way to easily link it to the "alternating" status of each row; to apply it, I'd basically have to manually change the text color of each cell every time a change is made to the data table (which would hurt performance a little). I suppose a single custom text color applied to all rows would be easier, though.

Found and fixed the bug (an incorrect validation order leads to any filters other than "_allrows" being rejected on import); I think that bug existed even way back in PortaBase 1.9. I'm inclined to save that bugfix for PortaBase 2.1; it doesn't show up in typical usage, it's been around for 6+ years, there's a workaround, and it affects all platforms so I'd need to do a full new set of installers for it. If some more critical bugs get reported, I'll put out a 2.0.1 bugfix release.