Is EPiServer Commerce 188.8.131.52 (CMS 6.1.379) the same as EPiServer Commerce 1 R2 SP2?
According to compatibility chart - yes. Just double check file version as well.
Here are my few experiences while upgrading, better if you can have a look, and add you experience also if you find any issues.http://world.episerver.com/Blogs/K-Khan-/Dates/2013/5/Programing-changes-required-while-Upgrading-Episerver-Commerce-R2-to-R2SP1-and-R2SP2---Part-1/
I have downloaded the update and followed the instructions:
From EPiServer Deployment Center i run the following:
EPiServer Commerce 184.108.40.206 (CMS 6.1.379.0)
EPiServer Commerce Sample 1.1 (CMS 6.1.379.0)
In the instructions I found this link confusing:
As I shown above I upgraded EPiServer but the link describes how to reinstall EPiServer from start.
The referenced dll files in my EPiServer Commerce Site must be updated to the new version. I have a question if any more changes must be done to the project?