I was referred to this forum (hopefully the right one).
I have finally succeded in installing Marketpress Lite and the plugin Web invoicing and Billing.
When sending an invoice notification to the client, I don't want to give the client the opportunity to pay via the invoice notification online, which can be done via the button "Process Payment". The rest of the notification is okay. I changed the email template to reflect this (I allow viewing and printing). Thus it makes no sense to have the button. Somewhere there must be coding that can be changed or deleted so as to remove the button "Process Payment" which appears not as part of the plugin's mail template, it seems - I can't see it in the email template at least.
I have almost no experience so please give the simplest possibe solution.
thanks in advance