checkout and user registration questions


I’m new to WPMU, and have been reading the forums for the last 2 days researching marketpress – and it seems to be an awesome plugin and ideal for a project I’m about to start (essentially, I’m trying to set up an Etsy-like site). Before I jump in, I do have a few questions I’m hoping can be addressed.

Regarding global checkout and chained payments, I understand this is not possible, but might be an added feature down the road. The last forum post I saw was from a few months ago, so I’m wondering (hoping) if there are any updates on this?

Taking a cut of user sales is fundamental to the site I’m building, so I guess I’ll have to use individual checkouts. My concern is that a visitor will add a product to his/her cart on one store, continue to shop around other stores, and then not be able to find their way back to their product to checkout. I’m probably overlooking something quite obvious, but how have others addressed this issue?

If I use individual carts, I can charge users a one-time fee to set up the store, correct?

Regardless of global or individual carts, payments between buyer and seller are strictly between buyer and seller, right? In other words, the network admin will not have to disburse payments?

In terms of users registering and setting up their own stores on the network, I was planning on using Gravity Forms for registration – is there a better way to do it, or can MarketPress handle it? Or do I need an entirely different plugin?

Once users are registered, will they be directed to their own admin panel to set up shop? I assume this is the way it happens.

Last question – I’ve used WP Multisite before, but only w/3 sites in the network. Are there any limitations to the number of stores that can be set up?

Thanks so much, and apologies for the long post – I just want to make sure I’ve covered my bases before my client commits. Can’t wait to get started w/MarketPress!