I am not aware of any Total Mix preset for this, but you can set this up easily yourself.  Since this is for your 2 bus, in Logic just send the mixed signal to any available playback outputs on the UFX.  For example, let's say in Logic you send your mix to UFX outputs 3/4.  In Total Mix you'll see this signal in the playback channels (middle row) on channel 3/4.  Route this playback signal to any available pair of hardware outputs (bottom row in TM), for example outputs 5/6.  Then take two patch cables and patch UFX outs 5/6 to your compressor's input, and route the compressor's outs back to any available pair of inputs (e.g., inouts 1/2) on the back of UFX.  Set up a new stereo track in Logic to record inputs 1/2, adjust levels in Total Mix as needed, and you are all set. 

I think some DAWs have a way to help set up busses for easy use of outboard gear.  Not sure if Logic does this or not.

Since you new to Total Mix, I encourage you to really read through the manual and play around with it. It can be confusing at first, but it begins to make sense quickly with some practice.  Routing is almost infinitely flexible.  Anything you can think of in terms of routing is almost certainly possible, the only limitations being the physical inputs and outputs.  This is a huge benefit to using RME gear. 

One tip that really helped me once I understood it - The names of the playback channels (middle row) have nothing to do with the physical ins/outs they reference and are always available even if the gear they reference is not.  For example, even if you don't use any ADAT gear, you still can use all the ADAT playback channels for whatever you need.  I find it useful to think of them not like they are labeled (e.g., "AN 1/2" or "ADAT 5/6"), but instead just "playback 1/2" "playback 13/14" etc. 

Enjoy!