specially transparent grid no!
grid is a simple vfp control and have no handle to support transparency.
-making a form embedding transparent (or semi transparent) grid: yes and transparency could be between 0-255(fully transparent to fully opaque).
this can be solved with API setLayeredWindow but its applied to all controls and form.
transparency is available for top level form only (or at least showWindow=0,1 and Desktop=.t.)
you have an example of form transparency in shipped vfp9 samples.

DO FORM home(1)+"samples\solution\sedona\fadeaway.scx"

or

DO FORM home(1)+"SAMPLES\SOLUTION\TOLEDO\IRREGULAR.SCX"

i have worked on grid transparency but with an artifact of 2 superposable forms.can see this in
http://yousfi.over-blog.com/2015/01/visual-foxpro-grid-with-background-image.html

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