Can I do initial testing all locally as it stands now (i.e. single user testing locally, just to see if the code works)
Yes. This is why we include the Developer SDK for free. It has 2 CALs (Client Access Licenses) and can be activated through the My Account area of the website. You will only want to activate once you know your host name (localhost, data.myserver.com, etc.) and know the MAC address of the machine on which it will be loaded.
Do you have a special trial license available?
This is why we provide the Developer SDK. You can use this SDK with a purchased or trial version of StrataFrame.