Finally, with version 1.10.0-5, conky started to work again and finally understood all commands of my configuration. All? Well, it still doesn't recognize 'pre_exec', but I substituted this command with an 'execi 3600', which will do for the time being. I've put the configuration file of my Lifebook here. For those interested in the weather, there's also a config file of a weather conky. Both look exactly as in this screenshot.
Update, 04/23/16: The weather conky is broken since Yahoo locked its weather API. The workaround posted here stopped working a few days later. Plenty of alternatives exist, but I haven't found the time yet to examine them.
Update, 04/24/16: Found another workaround. Let's see how long that one lasts...
Update, 01/03/19: It's dead, Jim. Important EOL Notice: As of Thursday, Jan. 3, 2019, the weather.yahooapis.com and query.yahooapis.com for Yahoo Weather API will be retired.