Nice game! As a fellow Colle Koltanowski player....
Look out for for 6...Nbd7 !? 7...c5 & 8...Qc7 with 9...e5 on deck!
A lot has been written about that line ... By Koltanowski... by Bronznik... etc IMO... I'm still not sure Black really gets a comfortable game. Sure he get's a comfortable opening phase... but if White has burned the midnight oil in these position , understands what to do with the 3:2 pawn majority IMO...Black is defending... every exchange makes the 3:2 majority even more pronounced... IMO the strategic and tactical yet out of typical Grunfeld piece play ( I just don't see the average Grunfeld player feeling optimistic or comfortable in these lines)
Normally I transpose into a color's reverses QGA, Semi Slav or Noteboom the moment ...c5 is played... but once in a while I'll get move ordered into this line. I use Nestler,V -Mueller,H Venice 1950 as my model game (For how I would play the position(s)
ElNegroCorazon... if you don't have Sergio Pandolfo's "The Colle System" you got to get it. Based on the Colle Koltanowski (not the Zuckertort) It's not a "how to play the Colle" It appears to be a repertoire ... (I'm assuming Pandolfo's own repertoire ) Many of the lines are very old school (like the one above) where people are not going to be booked up lines to play against them. It greatly eases constructing a solid repertoire around the Colle Koltanowski...
So this was a recent 10 minute rapid game playing the Colle against Black setting up a Grunfeld Formation. It's not the best example of playing technique for either side but at 34 centipawns loss, it is at least fairly decent.