Dear Becky,
Thanks for your interest.
There are several ways to upload your own map.
1 via direct manual upload
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If you zipped the shapefile you can directly upload by opening the Rstudio server under Process and use the upload button (bottom right panel).
Illustrated here: https://github.com/openforis/accuracy-assessment/blob/master/presentations/p_sae_design.pdf
You can do the same from the Jupyter server under Process
2 via FTP manager
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A more long term solution to upload and download files to/from SEPAL is to use a FTP manager such as FileZilla.
Go to File / Site manager
Open a NEW SITE
Then set parameters as follows:
HOST: sepal.io
PROTOCOL: SFTP-SSH File Transfer Protocol
PORT: 443
LOGON: Ask for password
User: your_sepal_username
Click Connect and you will have an interface between your desktop and your SEPAL environment
Hope it helps, let me know
Best
Rémi