I would suggest going by ID (international Drive) - (536)
turn right out of HGVC at the traffic light turn right again - stay on this road until it deads ends - then turn right again - go through 535 - you will pass the Marriott WOrld Center (BIG HOTEL) on your right - get in the left lane when you see this thing because the Nick hotel is on the left.
wrong way - oh well try again
at the Nick hotel - the you want to be on World Drive (ID or 536) - not IDS.
if the MWC can be seem - then you are going on the right road
anyway from the hotel turn right - get in the left lane once you are pass 535 - get ready to left at the next traffic light - I remember only 1 more traffic light - [before it gets to the Publix shopping mall (HGVC is across the street) on Vineland]. so at the 2nd traffic light (on ID 536) turn left - the HGVC is the second left turn (might be 3rd?)
I stayed at the Sea World one last year, and it took me 15 minutes with almost NO traffic to get to the Nick Hotel. The Tuscany one is even closer (we are staying there this year!).