Error while using FBA solution for two FBA Website Application

We were using FBA Management Solution on one of the FBA web application. Recently created a new FBA application on the same farm. We used the same DB for FBA user access. The feature got activated and shows the options under Site Settings > Users & Permissions.
While configuring new fba user, following message is appearing.

"The resource object with key 'UserMgmt_Title' was not found."

Help me to solve this error. Thanks.
It sounds like for some reason the FBA Pack solution was not deployed to the web application. In Central Admin, go to System Settings -> Manage Farm Solutions and ensure that the FBA Pack solution is deployed to the web application that you are using it on.
The FBA Solution was not deployed from the Central Admin. After deploying the solution everything worked perfectly. Thanks on guiding to right path.

we are having one more issue with using the FBA change password webpart. we created a blank web part page and insert the webpart. Now when we change password, we keep receiving the error message saying "password or new password is incorrect. new password should be 7 min characters......"

Please help with this.
The password length and complexity are set by your membership provider in your .config files. See here for details:
Configuring the machine.config solved the issue.
Thanks a ton ccoulson.

Appreciate you help. Cheers!!