Form key error! Submission could not be validated.

Here is some more information. On the local copy which I run on wamp server in development mode here are some errors. No emails are sent, only form confirmation appears and it deployed version only key submission error
contact form:
# Time Memory Function Location
1 0.0003 671464 {main}( ) ..\index.php:0
2 0.0004 676328 require( ‘C:\wamp\www\Advantage_Imports\wp-blog-header.php’ ) ..\index.php:17
3 0.1406 30900296 require_once( ‘C:\wamp\www\Advantage_Imports\wp-includes\template-loader.php’ ) ..\wp-blog-header.php:16
4 0.1436 31182872 include( ‘C:\wamp\www\Advantage_Imports\wp-content\themes\Advantage_Imports\page.php’ ) ..\template-loader.php:47
5 0.1799 31381024 the_content( ) ..\page.php:32
6 0.1799 31381448 apply_filters( ) ..\post-template.php:166
7 0.1805 31383168 call_user_func_array ( ) ..\plugin.php:173
8 0.1805 31383200 do_shortcode( ) ..\plugin.php:173
9 0.1805 31384048 preg_replace_callback ( ) ..\shortcodes.php:188
10 0.1806 31386024 do_shortcode_tag( ) ..\shortcodes.php:188
11 0.1806 31386456 call_user_func ( ) ..\shortcodes.php:273
12 0.1806 31386496 contact_us_shortcode_func( ) ..\shortcodes.php:273
13 0.1806 31387104 car_demon_contact_request( ) ..\car-demon.php:204

Error on submission
( ! ) Notice: Undefined variable: require_phone in C:\wamp\www\Advantage_Imports\wp-content\plugins\car-demon\forms\car-demon-contact-us.php on line 39
Call Stack
# Time Memory Function Location
1 0.0002 670840 {main}( ) ..\index.php:0
2 0.0003 675704 require( ‘C:\wamp\www\Advantage_Imports\wp-blog-header.php’ ) ..\index.php:17
3 0.1383 30898976 require_once( ‘C:\wamp\www\Advantage_Imports\wp-includes\template-loader.php’ ) ..\wp-blog-header.php:16
4 0.1410 31181544 include( ‘C:\wamp\www\Advantage_Imports\wp-content\themes\Advantage_Imports\page.php’ ) ..\template-loader.php:47
5 0.1763 31379696 the_content( ) ..\page.php:32
6 0.1764 31380120 apply_filters( ) ..\post-template.php:166
7 0.1768 31381840 call_user_func_array ( ) ..\plugin.php:173
8 0.1768 31381872 do_shortcode( ) ..\plugin.php:173
9 0.1768 31382720 preg_replace_callback ( ) ..\shortcodes.php:188
10 0.1768 31384696 do_shortcode_tag( ) ..\shortcodes.php:188
11 0.1769 31385128 call_user_func ( ) ..\shortcodes.php:273
12 0.1769 31385168 contact_us_shortcode_func( ) ..\shortcodes.php:273
13 0.1769 31385776 car_demon_contact_request( ) ..\car-demon.php:204

( ! ) Deprecated: Function split() is deprecated in C:\wamp\www\Advantage_Imports\wp-content\plugins\car-demon\theme-files\forms\car-demon-contact-us-handler.php on line 97
Call Stack
# Time Memory Function Location
1 0.0011 770320 {main}( ) ..\car-demon-contact-us-handler.php:0
2 0.1371 30917624 send_contact_request( ) ..\car-demon-contact-us-handler.php:26

( ! ) Deprecated: Function split() is deprecated in C:\wamp\www\Advantage_Imports\wp-content\plugins\car-demon\theme-files\forms\car-demon-contact-us-handler.php on line 170
Call Stack
# Time Memory Function Location
1 0.0011 770320 {main}( ) ..\car-demon-contact-us-handler.php:0
2 0.1376 30923840 adfxml_contact_us( ) ..\car-demon-contact-us-handler.php:68

( ! ) Warning: mail() [function.mail]: Failed to connect to mailserver at "localhost" port 25, verify your "SMTP" and "smtp_port" setting in php.ini or use ini_set() in C:\wamp\www\Advantage_Imports\wp-content\plugins\car-demon\theme-files\forms\car-demon-contact-us-handler.php on line 74
Call Stack
# Time Memory Function Location
1 0.0011 770320 {main}( ) ..\car-demon-contact-us-handler.php:0
2 0.1380 30925056 mail ( ) ..\car-demon-contact-us-handler.php:74

Service form

! ) Deprecated: Function split() is deprecated in C:\wamp\www\Advantage_Imports\wp-content\plugins\car-demon\theme-files\forms\car-demon-service-handler.php on line 128
Call Stack
# Time Memory Function Location
1 0.0059 823768 {main}( ) ..\car-demon-service-handler.php:0
2 0.1419 30972328 send_service_request( ) ..\car-demon-service-handler.php:27

( ! ) Notice: Undefined variable: html in C:\wamp\www\Advantage_Imports\wp-content\plugins\car-demon\theme-files\forms\car-demon-service-handler.php on line 288
Call Stack
# Time Memory Function Location
1 0.0059 823768 {main}( ) ..\car-demon-service-handler.php:0
2 0.1424 30975664 get_service_email( ) ..\car-demon-service-handler.php:29

( ! ) Warning: mail() [function.mail]: Failed to connect to mailserver at "localhost" port 25, verify your "SMTP" and "smtp_port" setting in php.ini or use ini_set() in C:\wamp\www\Advantage_Imports\wp-content\plugins\car-demon\theme-files\forms\car-demon-service-handler.php on line 96
Call Stack
# Time Memory Function Location
1 0.0059 823768 {main}( ) ..\car-demon-service-handler.php:0
2 0.1456 30981288 mail ( ) ..\car-demon-service-handler.php:96
Thank You
Your Service Request has been sent.
You should receive a confirmation from our Service Department Shortly.
The information you sent is below.
If you have questions or concerns please call and let us know.

Thanks Jay, I’ll wait until the new version comes out, meanwhile I replaced forms on deployed site with another plugin and I’ll revert once you upload new version.