New Romance Conlang - Roumán Part I, Intro and orthography

Inspired by Óskar's Thylean and Barry Garcia's Montreiano, I finally
decided to begin a con-romance lang.  However, the internal history is
completely improbable.

This language, provisionally known as Roumán, is spoken in the ruins of
Atlantis.  Long ago, the Atlanteans possessed great magical skills.
However, a group of powerful wizards had discovered the existence of
parallel Universes, and were experimenting in a way to cross between
universes.  However, their spell grew in power much too quickly,
transporting the entire continent to a parallel universe, destroying
many structures on Atlantis, and soaking up most of the magical energy
of both universes, rendering magic nearly powerless.  A portal remained,
and even today, traces of it remain as the Bermuda Triangle.  Anyway,
around AD 20, a group of roman naval ships got caught up by the portal
and were transported to Atlantis.  Once they realized that they were
stuck there, they set up a colony, and began a campaign of conquest,
establishing Provincia Atlantis.  Roumán is the descendant of Latin used
there.  It was influenced by the native languages, which were ergative,
and the society of the Atlantean Romans became more stratified,
reflected in the grammar.  I will describe primarily the dialect used in
Roum Nou, the capital.

Roumán

Vowels
a = [A], occasionally [@] in syllables immediately preceding the stress
e = /E/
ei = /e/ <-- ei is actually a ligature, resembling an E with a small dot
over it
i = /i/; [j] before a vowel or word-finally
ii or í = /i/ word-finally
o = /O/
ou = /o/ <-- another ligature, resembles a "Jesus fish" but facing
downwards
u = /u/; [w] before a vowel
Stress marked by an acute if not in penultimate syllable, and sometimes
orthographic, as in sóu, genetive plural masculine definite article

Several diphthongs exist: oe, eo, ai, au, ea, oa

Consonants
b = /v/
bb = /bv/ word-finally
     /b/ elsewhere
b' = /bv/ <-- ' indicates a cedilla in the "romanization", a dot in
     the native alphabet (which is a descendant of the Roman alphabet)
c = /ts/ before i or e
    /x/ elsewhere
ç = /ts/ <-- not actually a cedilla, actually a dot over the c
cc = /k/
d = /dZ/ before i or e
    elsewhere - in conservative dialects, /D/; in Rom Nou, /v/; in
    some dialects, /z/
dd = /dz/ word-finally
     /d/ elsewhere
d' = /dZ/
dl = /L/ (voiced lateral fricative)
f = /f/
g = /dz/ before i or e
    /G/ elsewhere
gg = /g/
h not used
k = /k/, an alternate to cc, obligatory when adjacent to ç
l = /l/
m = /m/, pronounced as /n/ when word-final
n = /n/ or homorganic to following consonant
p = /f/
pp = /p/
q not used
r = /l/ <-- etymology determines use of l or r
s = /s/
t = /tS/ before i or e
    elsewhere - /T/, /f/, or /s/ by dialect; /f/ used in Rom Nou
t' = /tS/
tt = /t/
tl = /K/ (voiceless lateral fricative)
st = /S/ before i or e
     /st/ elsewhere
st' = /S/
v not used
w not used
x = /x/, mostly only used word-initially, reflecting historical sc-
    (/sk/ -> /ks/ -> /kx/ -> /x/)
y = /Z/
z = /z/
zd = /Z/ before i or e
     /zd/ elsewhere
zd' = /Z/
/pf/ also exists, and is written {pf}