when submitting catalog  Request via USS,  as soon as the Submit button is pressed, it gets grayed out and you cannot do anything. 

Some  browser’s security setting blocks  the  security related messages and  prevent it from progressing further .    IE usually has very tight security setting  by default  .   

catalog 14.1

Check this setting on IE11 :

Tools -> Internet Options -> click Security tab. Your Security Zone level will be listed on this screen, by default this is set to Medium-high.  To change the setting for your message click Custom Level , locate the Access data sources across domains under the Miscellaneous section , it has the following options  :

*Disable

*Prompt

*Enable

1) With Disabled setting ,   you  can see this   problem  ( i.e.   "submit" button gets greyed out and you cannot do anything once you click "submit" button to submit a request  .

2)  With Prompt setting  ,    you can see  the  security  message  prompt  , click ok to continue ,  the request will get submitted successfully and it will work fine .  

3)  With Enable setting  ,      you will not   see any security  message prompt  and it works  fine .