So I was happily fighting for my team in LD...

And then this...
http://1.bp.blogspot.com/-vIUbn7ePT68/Ty05rZeA5dI/AAAAAAAAAOM/7AA6xQdwE3...
Got a bit angry there. I don't like that feeling. Yeah, names blurred out for obvious reasons.
I want to report but eh, idk where. Too lazy to find. ^^;
Sorry for the crappy post. Been a bad day for me, just need to vent a bit.

Just put it in the chat bar:
/report (Player Name)
This looks like a person impersonating a GM, not sure.
A question, did you leave after that match? Gave into the threat? o_o

@ Jamoo
Yeah, left the match. Trying to report. ^^;

The game doesnt have a command to 'check if random people host 3rd party materials'.
That guy admits to have run a 'check'. Now ban HIM for using some 3rd party software to 'check you'.

Sup Murex! who ever did that is a prick! set them on your ignore list!
Upload the unblurred image to an image hosting site (such as imgur), then send the link in through support.
Mind you, I dunno if they'll take an image as proof. If you report a guy with the in-game function, I wager it sends a log of what the guy was doing for the last X amount of time directly to the GMs, and is thus irrefutable proof. Just a picture is a lot weaker, and they might throw it out.

Reporting will send chat logs of the last x amount of minutes (I think it's three but I could be wrong) so yeah, if you'd reported him he'd have been punished. And don't give in to threats like that, especially if you know you're not doing anything wrong. OOO are smart enough to check the validity of these things, they won't just ban you because some idiot said you were cheating.

Hello Shuichi :)
Thanks guys, now I know better. I think I must've reported it too late though. I think was around 15-30 minutes after it happened...

Congrats! You met a bully. I'm betting you were beating them pretty badly and he tried to scare you off. There's no possible way he could "do a check" on your computer. Just ignore him.
~Gwen
Ignore it and move on. Nothing they can do to you.