why wont google maps work after resigning or recompiling?

this is because access to google's stuff requires an api key, stored in xml as a resource or perhaps in code, that is linked with the certificate of the app. if you modified and resigned it, the certificate is different and will not match the api key. you will have to get a valid key for the signature you are using.

you should already have your own certificate you sign everything with. this way if you release an updated version of the app, users of your previous modified version can update without needing to uninstall the old one first. if you don't already have your own certificate, follow the directions here: Signing Your Applications | Android Developers. you will need to use keytool and examples are given in the link.

once you're done or if you already have your own certificate, follow the instructions here: Obtaining a Maps API Key - Google Projects for Android.

when finished with that, and you have your own api key, decompile your apk with apktool so you can modify resources. you are looking for an xml file with a string like:

android:apiKey="3BCknOWFD_vyechU238a1f9YOWyYP2Z91CEfQWw"

or if it is created dynamically in code, you will see the initialization of a mapview object. the constructor takes a string as the second parameter which is the api key. here's an example:

# replace p2 with our api key here:
const-string p2, "3BCknOWFD_vyechU238a1f9YOWyYP2Z91CEfQWw"

# create the mapview object with our modified api key
# this line should already be here and doesn't need to be changed
invoke-direct {p0, p1, p2}, Lcom/google/android/maps/MapView;-><init>(Landroid/content/Context;Ljava/lang/String;)V