Here's another image mostly processed with StarTools. In this image, I used the Decon and Sharp tools to bring out the Ha gas details as well as the core. It really made a big difference, especially around the core. I also removed the stars with the Heal tool and layered a less stretched/more saturated version. They looked a bit too processed so I layered back in 30% of the original stars. I brought in the Ha data by Layering it into the L channel and into the R channel. I think the core is a bit too bright and may tone it down in some future version. In any case, I was pretty happy with the outcome and quite good seeing certainly helped.
http://www.astrobin.com/full/77296/C/
The SN is much less obvious in the processed/non linear stretched image so here it is from a single L sub with just a slight linear stretch. See the above link for the processed version. .