The parking is too small message depends on the scenery and the airplane wingspan as specified in the airplane.cfg.
Nothing has changed with this version so, it means the parking IS too small. Of course, it might not really be too small, the scenery developer might just have set it so for some reason, or by mistake, which is why you CAN override that setting in the GSX parking customization page, by setting the "Max allowed wingspan" parameter, or clicking the small airplane icon close to it, to match it to currently loaded airplane.
About the VGDS not recognizing the Dash8, we added it in the current Live Udpate.
About the Jetway, it works normally, but you must choose a jetway which can reach the fairly low door of the Dash 8. For example, KCLT Gate E2, which has special jetways made for regional planes.