Can't use DOS3.3 Launcher

[chngai@cs.cuhk.hk (Ngai Chi Ho)]

I have a Mac LC 575 with IIe card installed.  Though I can connect a
5.25 drive, it seems good if I can use DOS3.3 Launcher to have access to
5.25 image files.  But every time I run it (from BASIC.SYSTEM, for
example), it just say "Error: can't find startup file".  Going through
the manual, I realize that it should be launched from ProSel, so that
the "startup file" can be attached to it first.  But where can I get
ProSel?  Is it commercial software?  (If yes, then seems no hope, as no
more Apple II software can be found in Hong Kong....)

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+-------------------------------+-------------------------------+
 "Blue Quadra"                   Chinese University of Hong Kong 
 Computer Science Year 3 of 4    ngai-chi-ho@cuhk.hk             
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