Is this stuff suitable for developing ActiveX/dynamic DLL libraries /
drivers, etc. that are expected to provide also wit pop-up dialog forms
at a certain point? I mean this is going to be a DirectShow Source
filter with possibility to set up its input filter capabilities on
demand, so this is going to be a dll registered with Regsvr32.

Cheers,
P.

Hello,

I can only talk about Prof-UIS. We used it very intensively in several
products over the past few months.

The pure implementation of this product is good, but the documentation
is extremely brief and their tech support is not helpful at all as
soon as you face any problems, that are a bit more specific.

The concept of their library is a bit restricted, too. One simple
example: unlike Microsoft's dialog bars, which can be created on the
heap and as members of other objects and which can also have many
child windows, the Prof-UIS counterpart may only be created on the
heap and may only have one child. This seems to be a small detail but
if you have to port applications with hundreds of dialog bars with
several childs and created as members of other objects, then the
effort to port your application may be huge.

This is just an example of many and the answer of the tech support in
such cases ist usually "just follow our concept". They don't seem to
have a good feeling, what "time, effort and costs" mean for their
customers - they always look at it from a pure technical point of
view.

The only advise I can give is don't be dazzled by first feelings of
success and start a trial port of a more complex application, before
you decide.

Best wishes.