can't build

[freemind001]

Hello,
I'm trying to build grey cursors
npx cbmp -d 'svg' -n 'GoogleDot-Grey' -bc '#808080' -oc '#FFFFFF'
succeded, I can find images at bitmaps/GoogleDot-Grey/

but
ctgen build.toml -d 'bitmaps/GoogleDot-Grey' -n 'GoogleDot-Grey' -c 'Grey GoogleDot cursors.'
fails with
freemind@minty:~/Google_Cursor$ ctgen build.toml -d 'bitmaps/GoogleDot-Grey' -n 'GoogleDot-Grey' -c 'Grey GoogleDot cursors.'
[Fail] Error occurred while processing build.toml:
Traceback (most recent call last):
File "/home/freemind/.local/lib/python3.10/site-packages/clickgen/scripts/ctgen.py", line 155, in process
cfg = parse_config_file(file, **kwargs)
File "/home/freemind/.local/lib/python3.10/site-packages/clickgen/configparser.py", line 190, in parse_config_file
config = parse_toml_file(fp, **kwargs)
File "/home/freemind/.local/lib/python3.10/site-packages/clickgen/configparser.py", line 148, in parse_toml_file
cursors = parse_cursors_section(d, config, **kwargs)
File "/home/freemind/.local/lib/python3.10/site-packages/clickgen/configparser.py", line 113, in parse_cursors_section
x11_blob = open_blob(blobs, hotspot, x11_sizes, x11_delay)
File "/home/freemind/.local/lib/python3.10/site-packages/clickgen/parser/init.py", line 22, in open_blob
return parser(blob, hotspot, sizes, delay) # type: ignore
File "/home/freemind/.local/lib/python3.10/site-packages/clickgen/parser/png.py", line 120, in init
super().init(blobs[0])
IndexError: list index out of range

please advice