Admin Error when saving Pages (not Posts) – Can’t modify header info

I’ve installed the plugin to implement custom Post templates which works nicely. However, I now get an error when trying to save a Page (not Post).

Here is the error I get when saving/updating a page:
Notice: Undefined index: tmpl_post_template_nonce in /Users/myusername/Sites/mydevsite/wp-content/plugins/templatic-singletemplate/post_templates.php on line 192

Notice: Undefined index: tmpl_post_template_nonce in /Users/myusername/Sites/mydevsite/wp-content/plugins/templatic-singletemplate/post_templates.php on line 192

Warning: Cannot modify header information – headers already sent by (output started at /Users/myusername/Sites/mydevsite/wp-content/plugins/templatic-singletemplate/post_templates.php:192) in /Users/myusernbame/Sites/mydevsite/wp-admin/post.php on line 198

Warning: Cannot modify header information – headers already sent by (output started at /Users/myusername/Sites/squidzink18/wp-content/plugins/templatic-singletemplate/post_templates.php:192) in /Users/myusername/Sites/mydevsite/wp-includes/pluggable.php on line 1216

Any insight would be great.

*Edit*

I deactivate the plugin and reactivated it and received an admin error: Warning: Cannot modify header information – headers already sent by (output started at /Users/squidz9/Sites/squidzink18/wp-content/plugins/templatic-singletemplate/post_templates.php:41) in /Users/squidz9/Sites/squidzink18/wp-admin/includes/misc.php on line 1114

• This topic was modified 8 years, 5 months ago by squidz.
• This topic was modified 8 years, 5 months ago by squidz.