I tested the latest khtml2png 2.7.6 on several boxes, running CentOS5 64bit, 32bit Ubuntu 8.4.2 and Kubuntu 8.4.2 with various versions of Adobe Flash 9 and 10 and Gnash.
Unfortunately, I managed to capture Flash content only on limited number of sites, using Gnash. When Konqueror is configured with Adobe flashplugin, all seems to be fine, while browsing most of the sites. However, whenever I try to capture site using khtml2png, the tool generates some error messages on the console. The captured image displays gray areas where the flash content should be.
Bellow is a typical log from a session:
../khtml2png2 http://www.youtube.com yt.png
(process:27735): Gtk-CRITICAL **: gtk_clipboard_get_for_display: assertion `display != NULL' failed
Adobe Flash Player: gtk_clipboard_get(GDK_SELECTION_PRIMARY); failed. Trying to call gtk_init(0,0);
X Error: BadWindow (invalid Window parameter) 3
Major opcode: 10
Minor opcode: 0
Resource id: 0x4600003
The errors appeared to be very similar to the already reported by other users on this board, suggesting khtml2png cannot initialize the plugin correctly .
I wonder if anyone can list his/her fully working configuration setup. As capturing flash content is of high priority for us, I will try to reproduce it as close as possible.