alignment tag

Keynote > Preferences > Rulers: deselect the Show Size and Position option

The size and position information can be turned off in Keynote 5 and all versions of 6.

What version are you using?

Try resetting Keynote; perform all the steps in the order listed:

1. remove Keynote version 6.5, you must use an application removal tool for this procedure to work: Appcleaner is free, I use Appzapper
2. empty the trash
3. shut Down the Mac (Apple menu > Shut Down)
4. wait 10 seconds, then press the power button
5. Immediately after you hear the startup tone, hold down the Shift key,
   release the Shift key when you see the grey Apple screen
   start up will take a few minutes longer than usual as the Mac is performing a software repair
6. restart the Mac normally, (don’t hold down any keys during startup)
7. install Keynote from the Mac App Store

Ah yes now I see your grab, these are connection lines, they are forced to show angle and vector pixel.

I guess they are forced to stay on as they display vector information.