This is Nico's riff from Silvered Shadows.
Any changes are welcomed as I am not musically educated and this may not be perfect. 
Nico uses a 7 string but I'm not certain if he uses the extra string for this riff. 
I have tabbed it out on my 6 string and it sounds right to me.
Tempo: 180 
Tuning: Drop A (A,E,A,D,F#,B)
Key: A#/Bb
[Nico's Riff]
3/4 Time
B|---------------------10-|-8----------------------|
F#|----------------11-----|----11--10--------------|
D|-------------10---------|------------12--10------|  x2       
A|------8--12-------------|--------------------12--|
E|--10--------------------|------------------------|
A|------------------------|------------------------|
B|---------------------|------------------|--------------------|------------------|
F#|--------------11----|-10b11br10b11br10-|--------------11----|-10b11br10b11br\--|
D|--------10-----------|------------------|-------10-----------|------------------|
A|-----8------8------8-|------------------|----8------8------8-|------------------|
E|--6------------------|------------------|-6------------------|------------------|
A|---------------------|------------------|--------------------|------------------|
B|-------------------|-------------------|------------------------|------------------------|
F#|------------------|-------------------|------------------------|------------------------|
D|--------5-----5----|-------5-----5-----|---------17------17-----|---------17------17\10--|
A|-----3-----3-----3-|----3-----3-----3/-|-----15------15------15-|-----15------15---------|
E|--1----------------|-1-----------------|-13---------------------|-13---------------------|
A|-------------------|-------------------|------------------------|------------------------|
            Let ring   ->                           Let ring      ->
B|---------------------|------------------|-----------------------|------------------|
F#|-------------10-----|-10---------------|-------------10------10/11----------------|
D|--------9/11------11-|-------11---------|-------9/11------11----|------14----------|
A|-----7---------------|-------------7----|----7------------------|------------12~\---|
E|--5------------------|------------------|-5---------------------|------------------|
A|---------------------|------------------|-----------------------|------------------|
                                           

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| b   Bend
| br  Bend release
| /   Slide up
| \   Slide down
| ~   Vibrato
| ->  Ring until end of measure
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