Sorry about the late response but I was in Seaside Oregon for a nice long weekend with the family.
As far as where you can or cannot run your boat is up to your discression but I will give you an idea (I will be giving instructions as if you were headed down river from High Bridge, i.e. lefts and rights). With a boat such as yours you can go pretty much anywhere you want on the main river (Snoqualmie/Snohomish). There are only a couple of stretches that may give you trouble, the first is one that I am sure that you have tackled and that is about midway between High Bridge and 522 and is full of logs an stumps which change position every year with floodsstretch that may give you problems is about 1/2 mile below 522 there is an island and if headed down river you want to stay to the narrower side to the right because the wide left side is very shallow during summer months. The next trouble spots are around Crab Bar and Thomas Eddy. The stretch right before you enter the eddy is extremely shallow, but only during the latest days of summer. And also right after you pass Crab Bar there is a pretty tricky section on a long but sharp bend in the river that has a lot of stumps that you need to navigate through (changes year to year). After this stretch you are entering tide effected waters and you need to watch the tides and don't get over confident just because you made the same line a couple hours before. (FROM JUST BELOW CRAB BAR DOWN THE RIVER IS EFFECTED BY TIDES SO BE CAREFUL).
Your boat should be able to run the lower Skykomish if the river levels are not to far down but be warned the lower Sky changes dramatically from year to year and almost never has the same line that you navigated the prior year. If the levels are way down don't even attempt it unless you are an expert boater. A couple of years ago my brother and I rescued two different parties of people on this stretch (and when Isay rescued, we actually saved thier lives), not including the search and rescue/fire department that we also bailed out of a sticky situation. So I warn you this is not a section of water to be taken lightly, use extreme cation.
If you have not much experience running the rivers then all you really can do is get out and practice and learn how to read the water which is the most important thing about boating and fishing a river. Don't get discouraged when your boat bottoms out or whacks a rock, log or sucks stuff into the impeller, that is all part of running a boat in a river.
The maps I have provided are loosely drawn off of a Thomas Guide and have a bit of my own interpretation thrown in. One map is from High Bridge to 522 and the other is from 522 to French Slough which is in between Thomas Eddy and Snohomish. I marked spots of caution that are difficult with RED and care should be given in these areas. Also I have marked down with big black arrows which direction you should take around the islands.
Really the best thing that you can do is use your own discretion when it comes down to running a river. IFyou don't feel comfortable doing something, then don't do it.
Sorry about the crappy maps, they were hand drawn and had their picture taken by a horrible camera.
](./images/smilies/eusa_wall.gif "Brick wall")
