I have thought about what can be better for modplug, and I thought of one vst-plugin concerning the whole song.
there allready is a reverb effect, but it makes the quality of the song even worse.
Or two plugins per channel might be a solution, I don't know nothing about c++, so maybe it is impossible, it would be splendid if it is possible.
I also use reason to make sample, because that program can use more effects on one channel
I'm not entirelly sure what you mean by what you've written, but if it is what I think it is, then the answer lies whitin this topic:
http://forum.openmpt.org/index.php?topic=1392.0
If not, feel free to ask any question. :)
To use a vst affecting a whole song, you just need to check the box "Master" in the General tab, "Mix setting" section. So, as there are very good (and free) vst out there, it is not worthy developping specific ones for Modplug. And about using several vst in one channel, it is really very simple to do it. Only remember to put them in order (vst in slot 1 can be routed to vst in slot 2, but not the other way).