Shamim's Plugins

You can activate license in subdoamin dev and staging for development for free.
If you have to use softgrid subdomain for development you cannot activate license for free. In that case you can use without activating license there. You will get all functionality for testing.

Yes possible.
First get message id which title you want to change (parent message). Then use following code

$message = fep_get_message( 1 ); //1 is message id which title you want to update
$message->update( [ 'mgs_title' => 'UPDATED TITLE HERE' ] );

Can you login if captcha active and login form is checked?
Please again check your captcha version and keys in Settings > Advanced noCaptcha & invisible captcha > Google Keys are correct and same as google website.

If still not working please send me your captcha page url.

You can add following css in Front End PM PRO > Settings > Appearance > Custom CSS

.fep-form-field-fep_pro_to {
	display: none;
}

You can see this commit https://github.com/shamim2883/front-end-pm/commit/535a30e9de3dfa07a9cd9e2abd0e863d0efd90c2

Issue was not in the plugin.
You added some code in your child theme’s functions.php incorrectly. I have corrected it. Now check please.

you can pass in url like &field_name=field_value

Use options as key value pair. eg.

$currency = array(
		'USD' => 'USD',
		'EUR' => 'EUR',
		'GBP' => 'GBP',
	);