12 Volt Trigger/Amp Question??

Well I am rather new to separates and just realized I could use the 12v triggers between my Outlaw 950 and Adcom gfa 7400. Now it appears to be working fine, but my first question: is it ok to use this trigger between these two separates even though they are different brands??

Second question: Should the amp be on first or vice versa?? Basically is it alright for them to be turned on at the same time??
12v trigger is 12v trigger, regardless of manufacturer. It's no problem to use 12v trigger in a multi-brand system.

It's best practice to turn on the amp last. Some devices have a fixed or variable delay on the 12v trigger in. Most do not. If you use the pre/pro to send the turn-on trigger pulse to the amp, that should be plenty good enough.
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Well i do notice it makes a thud noise when I turn on the processor and it triggers the amp instantly, but I do this before turning on the cable box or source.

Is it ok for the speakers as long as the source is turned on last???? I just figure since there is no source it would be fine, but what do I know.
Hope my post to your query of remote powering an GFA 7400 helped. If your source isn't 12 volt triggered then have it on first.