To make it full screen, long press on the video, and press the rectangle that appears in the upperleft part of the video.
Correct, and I believe this was implemented in flash-beta2 & 3, if you are running beta 1 there is no full screen option.
I downloaded com.adobe.flashplayer-1.apk . How do I install it?
You need to run the file. If you do not have a file browser yet (why there is still no file browser in android, I dunno), get "astro file manager" free from the market. Browse to your sdcard/download folder, and click on the file. It will install it for you.
BTW, that looks like you have beta1, beta3 is the newest version.
When I go to the market and use the 3D barcode, it tells me it can't find the file. Anyone else? What am I doing wrong?
If you want it right away, try searching the web.
There are lots of reports on here that flash is not showing in the market. It seems the problem is not that flash is not in the market, but they haven't fixed it to show up. When you search the market, the market knows which phone/OS version you are using. (This is good because if you were using a G1 with 1.5/1.6, and an app was made only to run on 2.x, you wouldn't see it in the market). AFAIK flash was only available to Nexus One users who got the official update. If you did not have that phone/OS it would not show up. Motorola & Google dropped the ball by not having this ready for the OTA update, but I'm sure it will get fixed soon.