Really? Then I'd like to listen mp3 recordings of your "grag gedaan", "Nijmwegen" and "Spui" please!
Dutch grammatics is definitely easier than the German one, that's for sure, that and the syntax which is similar to English, that's why it may be easier to learn for native English speakers than Germans. My vocabulary is quite good and I can read 99% of written Dutch without any problems but understanding, let alone speaking, is a totally different matter.
About your German, hey, don't sweat it, I make mistakes in written and spoken English all the time but I guess most people are able to understand what I'm saying, and in the end that's all that matters, unless you want to write a book in German or Dutch or something.