It is done sequentially. All rules are carried out sequentially in order of appearance in the configuration file. Please note that with 1.12.0 (and above), rsyslogd has decoupled the receiver and the action configuration. So blocking actions do not have any direct impact on the ability to receive messages.
I'm new to rsyslogd so I need a bit more explanation...
Your answer means that the order doesn't really matter, I can choose which ever?
My concern, (being a bit paranoid ), is that I want to be so sure I possible can be, that the log messages are forwarded to the remote host without the possibility of being tampered with.