Message rates are set first by setting the overall message rate (200ms for 5Hz, 100ms for 10Hz) under CFG_RATES, and then individual messages can be set as multiples of that under CFG_MSG. For example if your base rate was 100ms, then if you set the specific RTCMv3 message type to “1” that would send every 100 ms, or 10 Hz. If you set it to 2, that would be 5Hz (200 ms). Set it to 10, and that would be 1Hz. Some messages are not required very often, like 1005, 1008, and 1230. Could set those to 100 which would be every 10 seconds.
I use MSM7 messages, which seem to work with my Trimble receivers. Not totally sure the difference over MSM4. 1Hz is enough for the MSM messages, 10Hz is enough for the antenna messages.