This is an app, it is not installed through recovery. Move it to your sd card via computer (USB wire) , then navigate to it though Astro or root explorer. Once you find it, tap on it and you will be asked if you want to install the app. When it has installed, you will then open the app and select ""install recovery". Once that happens you will get a screen on each boot up that allows you to go into recovery or boot normally. the instructions are at the location I posted earlier. Hope this helps.
Never mind, I miss read you post and thought you tried to install the app via recovery...It is getting late. Understand you will have to toggle safe mode to install new roms. Here is the link to better explain safestrap ->
How-To Safestrap « Hash-of-Codes
It might help with you problem.