[gentoo-science] cblas, blas, lapack

Hello *,

For a long time I was scared to switch to the 17.0 profile - I was sure 
that recompiling the world will be a difficult and time-consuming affair 
with lots of errors. Finally, I decided to switch my office ~x86 desktop 
(a rather old and weak desktop with a single-core pentium E5300). I was 
right - now most of useful stuff does not work. I am even more afraid to 
do it with my main computer - a ~amd64 laptop with a 4-core intel i7. I 
really need it to work normally.

OK, now a question. I'm trying to restore normal working of cblas, blas, 
lapack and all programs based on them. I use the science overlay. I've 
removed (by force, with -C) cblas-reference, blas-reference, 
lapack-reference and the corresponding virtuals. I try to follow

https://wiki.gentoo.org/wiki/User_talk:Houseofsuns

I've installed app-admin/eselect::science. Emerging 
sci-libs/blas-reference::science fails with sandbox violation on trying to 
mkdir /etc/env.d/alternatives/blas. If I create it by hand and try again, 
then sandbox violation on mkdir /etc/env.d/alternatives/blas/reference. If 
I remove sandbox from FEATURES in my /etc/portage/make.conf, nothing 
changes - still sandbox violations.

How can I emerge blas-reference::science?

Andrey