Hi Agracier
When your making Mymap_c in Microdem make sure lakes and rivers are ticked
in the big reflectance box, Azimuth 0 change water colour to black and check gray in the colours list I think 4 boxes you will see but just check grays.
Your Mymap_c should have black ocean grey land areas and black rivers and lakes.
You then use threshold in a photo program to change the gray to white as in a normal Mymap_c
Your rivers and lakes will come out reasonably well on a Mymap_c in Microdem.
Some will also show as black dots (connect the dots on a template and you have a river).
However they do need to be adjusted with a rivers template like you usually do.
Some can be broken in places.
I just made a map of Trinidad and Tobago with a massively large river system in
Venezuela. This system came out ok but needs some detailing work on a template.
At least it gives you half a chance with rivers at the beginning of a project.
And back to the height of water that can be done from what you suggested for map_h in another thread.
Here's a Mymap_c which has been made in Microdem and finalized in Gimp.
You can see some river systems and a huge lake.
You can also see some faint outlined rivers and connect the dot style rivers
Cheers Kirby