Good point about the slider, Greg--I was using a double-sided slider, so didn't think mattered.
I tried shoving both ends in, and just couldn't get it--obviously, I had the slider wrong side up. Just tried it again right side up and it worked fine--as you say, no starter strip required.
I may be the only person on BPL who's had problems with this--I searched for a how-to thread here, and didn't find anything. Found another video that recommended removing the teeth from both sides for an inch or so, and using the fabric as a starter--that seemed way too time consuming.