No, that is not the case. It is not a 0-100 interface. The 0 to 100 represents PERCENTAGES, as I mentioned earlier. The actual values being sent to a plugin range from 0.0 to 1.0. If a particular parameter in the plugin handles 128 values (such as any CC value, or a program change value), then it will scale the floating point range 0.0-1.0 into the integer range 0 - 127.
Your OSC 0-1 world is in fact a 0.0 to 1.0 world and it IS communicating with a MIDI 0-127 world.
You can easily see this by associating a widget with an OSC name and then examine the values sent out as you move the widget.
I did this with a simple MaxMSP patch that receives values coming from a widget and displays both the raw value (floating point between 0.0 and 1.0) and a scaled integer value between 0 and 127. When I move the widget with the mouse, you can see the raw values and the mapped values change. If I hold down the CMD key, I get an even finer grain movement and I can produce hundreds of floating point values all of which will still only scale to 0 until I get high enough.
I made a quick video of this and uploaded it so you can see it here.
If you are using a physical controller with a slider (say) that generates CC values between 0 and 127, then you’ll find that Gig Performer will restore that exact value, even if it doesn’t look like the widget has moved.