>>>Do you want users to associate the cutdown version with current full version (i.e. does the name need to be similar to the existing >>one/s) ?
>
>It's a difficult balance, we want to offer an upgrade path, so there has to be a connection but we don't damage our own sales of the full product by people thinking they can "down size" and get same product.

Then probably best to choose a name (and marketing strategy) that *emphasizes* the 'cut-down' nature of the product - after all you're not likely to lose sales of the cheaper version just because it is known that a more fully-featured (albeit more expensive) option is available.

To that end, much as I personally dislike the term, 'Light' might be a good option. Isn't 'Express' usually used with MS products - I'm not sure the wider public have the same perception of the meaning.

Other than that there are the usual suspects : 'Smart. Quick, Easy, Basic etc....
Or you could go for a completely different, catchy name and still advertise the connection to the full-blown option.