When you wind down a mag, when it's down to tucking height you're supposed to gather up the slack in the front panel and roll it up then push it down into the slot in front of the sissor arms for that purpose, repeat for the back panel, makes sure the fabric doesn't get caught up in the mechanism. Sounds like you just push it in through the gap in the sissor arms? As you got your second hand maybe you weren't shown the recommended way.I wondered how you got on with reaching across and rolling that front fabric up but I don't think you do?