Thanks for the responses!

Writing our own engine is out of the question, we have enough work as it is. And we are really not experts in low-level programming. Actually performance is OK with DelphiX (it runs at 20fps, which is sufficient for this type of game). We sorely miss alpha-blending though. Which is very slow without HW acceleration and with HW acceleration even the latest build of unDelphix is unstable.

Which engine would allow us to continue using standard forms? I really like Asphyre but it does not seem to work with forms at all.
We use DirectDraw in Undelphix with no HW acceleration. Is it possible to have HW acceleration + forms?

We need a form on the left side (or the DirectX part can be a window on the right). We also use pop-up forms, but while they are up we do not need any animations.

If you have any idea which enginge would do the above...

You can check out our games (1848 and For Liberty!) here:
http://www.battlefront.com

1848 is FREE and For Liberty! has a demo. You can check out the technology in both. Both are about 100MBs.