Assuming you have ADB access to your test device, you can issue the following command:

adb shell pm uninstall PACKAGE

Where "PACKAGE" is the package name of your launcher app (you should know this since you're creating the app in the first place.)

Assuming you have ADB access to your test device, you can issue the following command:

adb shell pm uninstall PACKAGE

Where "PACKAGE" is the package name of your launcher app (you should know this since you're creating the app in the first place.)

[Edit]
As requested, re-posting my comment as the answer: Every site for ZTE Blade has instructions for accessing the Fastboot mode via Volume Up + Power button combination. Eg: http://wiki.cyanogenmod.com/index.php?title=ZTE_Blade:_Full_Update_Guide Give that a shot and see if you can access the phone via fastboot.exe (should be in the [Android SDK]/tools/ directory.) At that point you can flash a different recovery image (Clockworkmod, Amon-Ra) that will allow access to /data/app to delete your program.