I have the same wall type for new and existing. I would like the ability to turn off the siding pattern in the existing phase and leave it on in the new phase. I would also like the ability to make the existing a siding grey tone while the new maintains the normal settings.

Currently we have the ability to display the siding as a grey tone pattern on the monitor display but when you plot the material settings define the plotted out put thus providing you with the normal line weights and settings for both the new and existing. You can create fills which have color assigned - but not define a Fill Pattern with color from under the settings menu I hope this is clear on what we are trying to achieve.