Hey Arya,
I not only know this is possible, I know that you have a project with an example. To achieve this, you will need to set your project to use HTTP POST, add the expected input variables, and call the URL with additional arguments.
To enable HTTP POST, you will want to add the following line towards the top of the web.config file:
<configuration>
<system.web>
<webServices>
<protocols>
<add name="HttpGet"/>
<add name="HttpPost"/>
</protocols>
</webServices>
</system.web>
</configuration>
Then, once the input variables are configured on your project, you will now have to modify the URL that you are passing to access the forms project. For example, if the two input variables were SomeTitle and TicketNum, the URL would be something like:
http://servername/projectname/composer.aspx?SomeTitle=stuff&TicketNum=777
Let me know if you can't get this to work.
-Aaron