I am using Adobe Audition 1.5 with Reason 2.0 rewired in for bass, drums and keyboards.  My computer has a Pentium D 3.2 Ghz processor and 2 GBs RAM.  My audio tracks are recorded at 24/96 using a Presonus Firebox audio interface and include mainly acoustic guitars, electric guitars and vocals.  I really want to use Marquis compressors and GlissEq on most bass and individual drum tracks with Voxformer on vocals and guitars.  Most songs have between 15 and 30 tracks each.  My problem is that running even a few instances of Marquis compressor completely overwhelms my system.  What can I do?  How many instances of these various plug-ins can I hope to run?  Does the 24/96 audio use more CPU to process?  Is there a mode for Marquis that will use less CPU?  Surely people are using more than a couple instances of Marquis and GlissEq in their mixes-what am I doing wrong?

I've just answered via e-mail.

This issue is probably unavoidable.  Marquis Compressor is indeed pretty CPU heavy.  You may switch to 'Clean' sound mode to preserve CPU resources.  96k requires more resources than 44.1k as well.

As for the GlissEQ, you may try to use Dyn 0 mode for maximum performance (though, the sound will be different a bit).