Reviving an old thread, I'm having this same issue.
I tried adjusting this different envelopes, as guyaguy suggested, but that didn't work.
One work-around is to increase the release on amp envelope, but that's not what I'm trying to do.
• I'm trying to use the Glide with the Arp, but the length of the note won't connect the two notes properly (in legato fashion).
I'm not seeing the 50% length anywhere for adjustments. Maybe it's right in front of me and I can't see it.