I don't believe there's an easy way to tell Procomm to use the modem on COM1, since Procomm considers the connection as a whole rather than a particular modem on a particular com port. What you can do is use set modem connection 10, which should make Procomm use the first modem on the system. I'm at work now and my machine doesn't have a modem so I can't test this, but that is what the help file states at least (I'm pasting the discussion below). I have a couple ideas for determing if a modem is on Com1 or not, but will not be able to test that until I get home.
modem connection index | string | CURRENT | FIRST
Specifies the active data modem connection. Either a zero-based index, or the name of a data modem connection in the Current Modem/Connection list in Setup, System, Modem Connection may be used. This command will fail if an attempt is made to set a Connection Directory entry to "direct connect-none", "direct connect-Telnet", or a modem/connection that has incnctlist set to OFF. This command will also fail if you specify a modem/connection that has incnctlist set to OFF. fetch returns the contents of the Current Modem/Connection field in a string.
Please note that the index value for TAPI connections begins at 10, even though TAPI connections may be displayed at the top of the Current Modem/Connection list. Other connections have zero-based indexes. For example, "direct connect-none" is always index 0, followed in order by the other connections in the list.
The CURRENT and FIRST keywords are valid only for a specified Connection Directory entry. The FIRST keyword is valid only when accessing a Fax entry.
aspect@aspectscripting.com