Try a new game today :)
The consensus appears to be that you can choose not to apply the effect on Experimental Train. I'm leaning toward that myself as I just reread the example on page 6: "If you choose to apply Distant Partners’ effects..."
Neither Distant Partners, nor Experimental Train are Action cards (they do not have the Action symbol). I was initially reading the rule about applying effects as literally as possible: "If the card you played is an Action card, you may apply its effects if you wish..."
It should probably read: "If the card you played has effects, you may apply them if you wish..."
Thanks, everyone who weighed in. :]
Enjoying the discussions and thanks for your understanding. It isn't easy to get everything perfect in the rules despite multiple outside players/proofreaders. However, I assure you that we did our best.