I've been fooling around with the template editing -- it seems to be very powerful although undocumented.

I do happen to be a developer but the templating system looks like it's on its way to being usable by anybody.

However, I can't get the invoice number to show up on an invoice. Is this not supported yet?

I have been able to get other dynamic text to appear where I like -- for example, the invoice total -- so I believe I'm doing everything correctly.

If you're trying to get the invoice number to appear when you are testing (previewing) your design, you won't be able to. In fact, you won't even see the invoice number when previewing an invoice you are about to send. In the current beta of Billings, you only see the invoice number on the actual, final PDF output.

HTH,

Where is first invoice number set? I suppose Billings2 increases this number by every invoice?

Information about invoice numbering is available in Billings Help (choose Help > Billings Help and search for invoice number). It's also mentioned in the Quick Start Guide which came with Billings: http://www.billingsapp.com/support/Billings2QuickStartGuide.pdf.

Invoice numbering can be customized in Billings Preferences. Choose Billings > Preferences, and be sure that you are on the General pane.

Billings does increase the number with each invoice. You can use special characters to represent day, month, and year, if you want your invoice number to reflect the current date. These characters are documented in the aforementioned Quick Start Guide.

HTH,