The SCXI-1127 was not designed for scanning though current measurements, but here are a few suggestions.
First, you need to make sure all the channels are set in 1-wire mode in MAX. Second, if you connect each branch to each channel, they will all be open except the one being measured. If the measured branch requires other branches to complete the circuit the current will not flow as expected.
Also the SCXI-1127 can only operate in the Break Before Make mode. For current measurement, it is preferable to use a Make Before Break switch module.
Make sure you do not exceed the current rating of the SCXI-1127 which is 1A switching and 2A carry.
Regards