I have been completely frustrated by 2.6. 15.0x workes OK. 26 says it can't find the printer on the USB but it can and actually start printing after a long delay. Still say no printer attached while printing.
Also, 2.6 seems to corrupt the existing 15.x settings. Changed the layer height to 0.0 and 15.x then gets divide errors in a python file. It spews a tons of messages. The useful ones are hidden in the massive spam.
I use Linux so I guess I could download and build from scratch. Think I will wait for stability.