(It wouldn't let me go back farther than 1.7.5) If this is a duplicate, please direct me to the original report. I did look around, and found nothing.
I want to use the new launcher to play older, more simple versions of Minecraft. Upon selecting old b1.5_01, it downloads and launches properly, but upon playing, I start to walk and can't stop. I take my hands off the keyboard and I'm still walking. I finally stop after a few seconds, and try again. Same thing; I walk perpetually in one direction, and my character is unresponsive to any other controls. I can't jump or look around. HOWEVER, nothing else seems to be effected.
This is the same in almost ALL Old Releases, Betas, and Alphas.
The old versions are not supported. Also, this sounds to be more of a technical support issue. For technical support please use the Mojang Support Center.