Converting Spamassassin rules to rspamd

I set up a new mail server using rspamd. I have sets of rules from spamassasin.

I would like to import/convert them to rspamd. What I did:

• Created file with rules on /etc/rspamd/custom/spamassasin.map

• Added config in local.d/spamassassin.conf:

  ruleset = "/etc/rspamd/custom/spamassasin.map";

• Restarted rspamd

In logs there are errors:

#1(main) <83zuwt>; lua; spamassassin.lua:871: unknown function Subject:raw=~/=\?(UTF|utf)-8\?B\?4(p|q)/
#1(main) <83zuwt>; lua; spamassassin.lua:871: unknown function From=~/Administrator/
#1(main) <83zuwt>; lua; spamassassin.lua:871: unknown function To=~/Recipients /
#1(main) <83zuwt>; lua; spamassassin.lua:871: unknown function Subject=~/(?: darmo| gratis|bez op.{1,8}at)/
#1(main) <83zuwt>; lua; spamassassin.lua:871: unknown function Subject=~/\-\d+\%/

Rules are fetched from: https://github.com/zabojcaspamu/spamassassin_rules/blob/master/local.cf.reguly.ZABOJCASPAMU and looks lik:

header   ZABOJCASPAMU_SUBJECT_KREDYT  Subject=~/(?:(K|k)redyt| po.{1,8}yczka)/
describe ZABOJCASPAMU_SUBJECT_KREDYT  W temacie slowo kredyt lub pozyczka
score    ZABOJCASPAMU_SUBJECT_KREDYT  0.8

Question is how to make it work or how to write/convert this rules to rspamd format. I didn't find a similar way as in Spamassassin on rspamd documentation.

It seems I've seen something similar in the past - does this error disappear if you add spaces around =~ operator in SA rules? If yes, then could you please open an issue in Rspamd bug tracker: https://github.com/vstakhov/rspamd/issues ?