The Portal has limited capabilities as far as editing the VSI. Its by far easier to edit the VSI in the Workstation for the things you want to do. For the VSM, you'll have to use the Workstation to add steps it.
A VRS file is a "virtual recording scenarios" file: when you record a VS, on the last dialog of the recording wizard, you can save your recording configuration (the ports, protocols, DPHs that are added, etc.) to make it easier to rebuild a similar VS using the same information. For example, if you start a new recording, there's a button around the bottom left of the first screen of the recording wizard to load a VRS (look for the tiny blue folder icon near the side-bar and just above the button bar); click that to load a previous VRS file. Having loaded it, all the screens of the recording wizard will be pre-populated with whatever values were saved in the VRS. As you step through the dialogs, you can change values as needed without having to redefine all your configuration parameters.
The button to save your recording information, will which create the VRS file, is very easy to miss. On the last screen of the recording wizard, on the screen that has the "Finish" button, look for a small icon that looks like a floppy disk icon; its just above the "Finish" button. If you hover over the button, it has a tool tip that reads something like "Save the recording definition to a local file". Click that and a Save Recording Session dialog will open, which prompts for the name of the VRS file and the folder in which to save it. In 9.5.1, this file was saved with the ".vts" extension, which is a binary version of a VRS. In 10.0, we changed the extension to ".vrs" and made it an XML file, so its editable. As such, you can make copies of a VRS, edit it in a text editor, change parameters as desired, save it under a new name, thereby creating a small collection of VRS files.
For MQ, here's a link to a short tutorial:
Tutorial 3: JMS Virtual Service Using DevTest Workstation - DevTest Solutions - 10.1 - CA Technologies Documentation
Hope this was helpful.
Regards,
Jon