Ricoh Imaging has uploaded most of the online seminars to Youtube.
They don't have subtitles, but you can use the Youtube auto translate function to get some idea of what they are talking about, or just for comic effect.
To access them, look on this page and click the newly added red buttons below the photographs of the speakers.
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Strangely the one that is missing is the one about the J-Limited. I'm not sure why that is.
If you want to see the part about the DA* 16-50, go to the last 10-15 minutes of the Iwasaki/Ikenaga presentation.
For information about the K-3 III, the Takashiro/Tanaka discussion may be of interest.
The presentation by Yoshiaki Kobayashi contains a lot of images he shot with the K-3 III and is nice if you like snowy landscapes.