I know this is a report on an older non-beta release, but thought it might be worth reporting.
I copy/pasted the application log from inside the app over to notepad for review, and noticed it mentioning where it was saving other logfiles - in C:\Users\Tom\.kivy\logs :
[Kivy ] v1.9.0
[Logger ] Record log in C:\Users\Tom\.kivy\logs\kivy_16-02-16_37.txt
[Python ] v2.7.9 (default, Dec 10 2014, 12:24:55) [MSC v.1500 32 bit (Intel)]
[Factory ] 173 symbols loaded
[Image ] Providers: img_tex, img_dds, img_gif, img_sdl2, img_pil (img_ffpyplayer ignored)
[OSC ] using <thread> for socket
[Window ] Provider: sdl2
etc etc etc
So I went to that folder while 1.4.2 was running, and it's dropping 15-25 new logfiles per minute in the folder, all only 3-4 lines long, all looking like the app is continually restarting. Most have 3 lines, some have an extra error line.
[INFO ] Logger: Record log in C:\Users\Tom\.kivy\logs\kivy_16-02-16_170.txt
[INFO ] Kivy: v1.9.0
[INFO ] Python: v2.7.9 (default, Dec 10 2014, 12:24:55) [MSC v.1500 32 bit (Intel)]
[INFO ] Logger: Record log in C:\Users\Tom\.kivy\logs\kivy_16-02-16_171.txt
[INFO ] Kivy: v1.9.0
[INFO ] Python: v2.7.9 (default, Dec 10 2014, 12:24:55) [MSC v.1500 32 bit (Intel)]
[ERROR ] Comms: Exception in connection_process_message_writer caused by SerialTimeoutException('Write timeout',)
Note that these are in addition to the one listed above (16-02-16_37.txt) which is also open but (properly) continues to grow as time goes on.
tom