Thanks for pointing the broken link out, I changed it.
I just tried the vertex sample, here's my output so you can see exactly what I did, it worked perfectly:
C:\pspdev>set PSPDEV=C:/pspdev
C:\pspdev>set PATH=C:\Python24\.;C:\WINDOWS\SYSTEM32;C:\WINDOWS; C:\WINDOWS\SYSTE
M32\WBEM;C:\WINDOWS\SYSTEM32\WSG32\;C:\Program Files\Subversion\bin;C:/pspdev/bi
n;C:/pspdev/bin;C:/pspdev2/bin;C:/pspdev/bin;C:/pspdev/bin;C:/pspdev/bin
C:\pspdev>set PSPSDK=C:/pspdev/psp/sdk
C:\pspdev>cmd
Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.
C:\pspdev>cd psp
C:\pspdev\psp>cd sdk
C:\pspdev\psp\sdk>cd samples
C:\pspdev\psp\sdk\samples>cd vertex
The system cannot find the path specified.
C:\pspdev\psp\sdk\samples>cd gu
C:\pspdev\psp\sdk\samples\gu>cd vertex
C:\pspdev\psp\sdk\samples\gu\vertex>make
psp-gcc -I. -IC:/pspdev/psp/sdk/include -G0 -Wall -c -o vertex.o vertex.c
vertex.c : In function 'generateVertexBuffer':
vertex.c(125) : warning: unused variable 'batchScale'
vertex.c(124) : warning: unused variable 'vertexOffset'
vertex.c(122) : warning: unused variable 'colorOffset'
vertex.c : In function 'main':
vertex.c(602) : warning: too many arguments for format
psp-gcc -I. -IC:/pspdev/psp/sdk/include -G0 -Wall -c -o ../common/callbacks.o
../common/callbacks.c
psp-gcc -I. -IC:/pspdev/psp/sdk/include -G0 -Wall -c -o ../common/vram.o ../co
mmon/vram.c
psp-gcc -I. -IC:/pspdev/psp/sdk/include -G0 -Wall -c -o ../common/menu.o ../co
mmon/menu.c
psp-gcc -I. -IC:/pspdev/psp/sdk/include -G0 -Wall -L. -LC:/pspdev/psp/sdk/lib
vertex.o ../common/callbacks.o ../common/vram.o ../common/menu.o -lpspgum -lpsp
gu -lm -lpsprtc -lpspdebug -lpspdisplay -lpspge -lpspctrl -lpspsdk -lc -lpspnet
-lpspnet_inet -lpspnet_apctl -lpspnet_resolver -lpsputility -lpspuser -lpspkerne
l -o vertex.elf
psp-fixup-imports vertex.elf
mksfo 'Vertex Speed Sample' PARAM.SFO
psp-strip vertex.elf -o vertex_strip.elf
pack-pbp EBOOT.PBP PARAM.SFO NULL \
NULL NULL NULL \
NULL vertex_strip.elf NULL
rm -f vertex_strip.elf
C:\pspdev\psp\sdk\samples\gu\vertex>make kxploit
mkdir -p "vertex"
psp-strip vertex.elf -o vertex/EBOOT.PBP
mkdir -p "vertex%"
pack-pbp "vertex%/EBOOT.PBP" PARAM.SFO NULL \
NULL NULL NULL \
NULL NULL NULL
C:\pspdev\psp\sdk\samples\gu\vertex>
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