MW5 is a desktop GIS which is extendable using the plug-in architecture. It is using the MapWinGIS mapping control and is created from scratch in 2015 using new technologies like MEF and Dependency Injection making it small in size, robust and fast.
I just released the stable release of MapWinGIS v5.3
Please download and try it, and let us know on this forum if you run into trouble.
Most work has been done by @jerryfaust