Oh yes, try to go if you can. I'm sure there'll be someone there who can show you how the wrap works and let you have a practice. If you are able to email someone beforehand to let them know you're coming they're more likely to be ready for what will suit you, eg. stretchy wrap, maybe someone with prem experience.
The owner of www.bebecannelle.com has recently had a prem baby and something she'd posted on there mentioned that slinging a prem was best done by an experienced sling user as airway was particularly important. But don't let that put you off, and the slingmeet is sure to help you with positioning.
Recently a mum of a toddler and a velcro baby borrowed a stretchy wrap from my sling library. She commented that it looked like doing origami with a sheet but by the following week she had bought her own and was evangelical about the sling, so I hope a sling is just as useful for you!