Did you get a can of propane (or butane for filling cig lighters) and spray around the IC tubes and vacuum hoses while the car is idling? That is an easy way to check for leaks. If the idle "pops" when you spray around a connection, you've located the problem.
When you find the source, disconnect the fittings and re-seal the connection. Use some RTV Copper Gasket Sealer (sensor safe).
Most likely you will find the leak where the Intercooler connects to the IC tubes, unless you have had the supercharger top off. If the (plastic/rubber) vacuum lines are brittle, then just get some new lines at the parts store and replace them. (easy)
The boost leak may be related to the vacuum line that feeds the guage, unless you are experiencing some performance issues.
Give us some info on the performance symptoms. It may not actually be vacuum related.............