OS X 10.5.2; installed from hans' most recent two builds. (in case the newest one was buggy). I have used the build you linked to unsuccessfully. I have also tried removing the org.puredata.plist file from ~/library/preferences before installing with no success.
An update - the problem occurs whenever I open any new window - even a new patch. immediately subsequently pd-extended crashes once on load.
Another thing that confuses me is that I still get a default font missing report after installing the version that now uses monaco as the default - I am guessing the same problem may be causing pd-extended to fail to reach all these.
all my engineer friends make fun of me for being confused by crash reports, but I can't get much past the "bad access" and "kern invalid address" seeming to imply that the problem is with how pd-extended relates to mac OS X not something internal to pd-extended.
I have here's what it says for the openpanel crash:
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x00000000074fd008
Crashed Thread: 0
Thread 0 Crashed:
0 com.apple.CoreFoundation 0x95ef3be9 _CFDoExceptionOperation + 441
1 com.apple.Foundation 0x9267a6e1 _NSRemoveAltHandler2 + 33
2 com.apple.AppKit 0x91415ac0 -[NSFocusStack unfocusView:] + 135
3 com.apple.AppKit 0x914159d1 -[NSView unlockFocus] + 117
4 com.apple.AppKit 0x9162da96 -[NSMatrix drawCellAtRow:column:] + 90
5 com.apple.AppKit 0x9158244a -[NSMatrix selectCellAtRow:column:] + 978
6 com.apple.AppKit 0x91630003 -[NSBrowser selectRow:inColumn:] + 301
7 com.apple.AppKit 0x9162273d -[NSNavBrowserDelegate reloadChildrenForNode:] + 2197
8 com.apple.AppKit 0x91621e78 -[NSNavDataSource _reloadChildrenForNode:] + 67
9 com.apple.AppKit 0x9161f6af -[NSNavDataSource _handleChildrenChanged:] + 275
10 com.apple.Foundation 0x9264fcdc _nsnote_callback + 364
11 com.apple.CoreFoundation 0x95e5a9da __CFXNotificationPost + 362
12 com.apple.CoreFoundation 0x95e5acb3 _CFXNotificationPostNotification + 179
13 com.apple.Foundation 0x9267d0fc -[NSNotificationCenter postNotification:] + 124
14 com.apple.AppKit 0x9161f4be +[NSNavFBENode _postNotificationForEvent:notificationName:parent:child:fbeProperty:] + 542
15 com.apple.AppKit 0x9161f299 +[NSNavFBENode _postNotificationForEvent:notificationName:parent:child:] + 70
16 com.apple.AppKit 0x9161f24a +[NSNavFBENode _postNotificationForEvent:notificationName:parent:] + 63
17 com.apple.AppKit 0x9161e918 +[NSNavFBENode _reallyProcessNotifications:] + 700
18 com.apple.Foundation 0x926a9e0d __NSFirePerformTimer + 477
19 com.apple.CoreFoundation 0x95e779c2 __CFRunLoopDoObservers + 466
20 com.apple.CoreFoundation 0x95e78d25 CFRunLoopRunSpecific + 853
21 com.apple.CoreFoundation 0x95e79d18 CFRunLoopRunInMode + 88
22 com.tcltk.tcllibrary 0x0a077bd3 Tcl_WaitForEvent + 679
23 com.tcltk.tcllibrary 0x0a0557ea Tcl_DoOneEvent + 312
24 com.tcltk.tklibrary 0x0b011f20 Tk_MainLoop + 36
25 com.tcltk.tklibrary 0x0b01dd26 Tk_MainEx + 1513
26 org.puredata.pd.wish 0x00002acb 0x1000 + 6859
27 org.puredata.pd.wish 0x00002a7e 0x1000 + 6782
28 org.puredata.pd.wish 0x000029a5 0x1000 + 6565