Please provide what settings you have in CB AntiSpam > Parameters > Captcha > Modes > Internal > General. Seams like a configuration is causing a weird scenario for the captcha image generation that shouldn't be happening as you've the following error with your captcha image URL.
Code:
Deprecated: Implicit conversion from float 32.5 to int loses precision in /components/com_comprofiler/plugin/user/plug_cbantispam/component.cbantispam.php on line 628
Below is the default configuration for reference, which you can try resetting to.
Image Height: 60
Image Color Range: 0
Image Background Color: 255,255,255
Image Text Color: 20,40,100
Image Background Noise: Enable
Image Foreground Noise: Enable
Image Foreground Noise Color: 20,40,100
Image Font Type: EARWIGFA.ttf and monofont.ttf
Character Rotation Range: 13
Character Offset Range: 3
Character Size Range: 5
Deprecations and warnings shouldn't really be outputting on production sites though. Be sure that the live version of your site has Joomla debug mode disabled and error reporting set to None to prevent deprecation notices from breaking things.