Hi Raquel,
I just saw your message by chance and thought I'd chime in. Not all hddm-functionality may run properly for your machine because it seems that hddm does not support pymc3. So you would have to install pymc2. You can do that by "conda install pymc". It could also be because hddm only runs well for specific versions of packages it relies on (see herefor my notes below).
For me, getting hddm to work on Windows 10 was difficult as well, but once everything is installed it works reliably. I took some notes on the install process, I hope they will be useful to you.
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install anaconda 3.7 for windows 64bit
install the build tools for visual basic (important!)
in Anaconda prompt:
conda create -n hddmEnv python=3.6.10
conda activate hddmEnv
conda install pandas patsy
conda install pymc=2.3.7
conda install statmodels
pip install kabuki
pip install cython
pip install HDDM==0.7.3
# Now I have to downgrade pandas
pip install pandas==20.0.0
install spyder version 3.3.3 for the hddmEnv via Anaconda Navigator
launch spyder via anaconda navigator
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As you can see, that works for me for version 0.7.3, which was the current version at the time. I am not sure whether results will be same or different for the current version 0.8.0.
Cheers,
Thomas