Singapore (Time to process: 20 minutes)
I have heard of horror stories associated with this border crossing. However, maybe they were all with foreign vehicles travelling INTO Singapore, and not exiting.
I had no problems at all.
Firstly, if you are in a foreign registered vehicle, you do not need to observe the ¾ tank of fuel regulation as signposted on the Bukit Timah Expressway (BKE).
Follow signs for Johor, and at the end of the road, there are three options. Cars, trucks and buses. Unsure if there would be a height barrier on the car lane, I went through the truck route.
The first barrier you come to is the Immigration Control. As well as having your passport stamped, here you pay your toll for the Causeway, for which you use the Autopass card received earlier in the day at the LTA offices on Sin Ming Drive. (See Singapore Country Information for info on the LTA, Autopass, etc).
The lass on the counter asked if I was going to return to Singapore in the near future. A positive response led her to give me a fistful of Embarkation-Cards.
Proceed then to customs control just a bit further along. Your Carnet is reviewed and stamped. As with most other border crossings to date, there was only a cursory glance at the chassis plate, and a friendly smirk from the customs official.
Then over the Causeway to JB.
Malaysia (Time to process: 20 minutes)
Another straightforward crossing. The only thing to note is make sure you don't crush a motorbike. Malaysians working in Singapore cross the Causeway mainly by motorbike. Travelling the route daily, they treat the customs shed like a slalom course.
The Immigration Control is first. In the adjoining booth is the counter for a toll. They only accept Malaysian Ringits, which, in my humble opinion, is rather shortsighted. Not having ringits, I paid in Sing-$: the guy had no choice - he was getting Sing-$ or nothing. My expression made that much plain.
After immigration, park in one of the bays, and go to the local cabin, waving your Carnet. It's completed, without vehicle inspection, and you're back on the road again.